Three new species of Rhodomyrtus (DC.) Rchb. (Myrtaceae) from Papua New Guinea

Abstract

Three new species of Rhodomyrtus (DC.) Rchb. are described from Papua New Guinea: Rhodomyrtus longisepala N. Snow & J.McFadden, Rhodomyrtus guymeriana N.Snow & J.P.Atwood, and Rhodomyrtus misimana N.Snow. Detailed descriptions, information on distributions and habitats, and conservation recommendations are provided for each new species. A tabular summary of some key vegetative and reproductive features is presented for species of Rhodomyrtus sensu lato. A membranous testa for three species of Rhodomyrtus is discussed for the first time, as is the occurrence of densely-packed, hair-like fibres comprising much of the outer testa in some species. Large, dark-maroon coloured cells in the fruit of some species impart visible pits on the outer surface of the seed coats in the dried fruits. Gelatinous endosperm is reported for the first time in the genus Rhodomyrtus , being present in Rhodomyrtus guymeriana. Transitions between the typological distinctions of eucamptodromous and brochidodromous leaf venation types are discussed for Rhodomyrtus surigaoensis.